package com.atguigu.web;

import com.atguigu.pojo.Book;
import com.atguigu.pojo.Page;
import com.atguigu.service.BookService;
import com.atguigu.service.impl.BookServiceImpl;
import com.atguigu.utils.WebUtils;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
 * ClientBookServlet主要用于 【处理页码(改变url以达到访问不同页码)】
 * */
public class ClientBookServlet extends BaseServlet {

    private BookService bookService = new BookServiceImpl();

    /**
     * 处理分页功能
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void page(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1 获取请求的参数 pageNo 和 pageSize
        int pageNo = WebUtils.parseInt(req.getParameter("pageNo"), 1);
        int pageSize = WebUtils.parseInt(req.getParameter("pageSize"), Page.PAGE_SIZE);
        //2 调用BookService.page(pageNo，pageSize)：Page对象
        Page<Book> page = bookService.page(pageNo,pageSize);
        page.setUrl("client/bookServlet?action=page");
        //3 保存Page对象到Request域中
        req.setAttribute("page",page);
        //4 请求转发到pages/manager/book_manager.jsp页面
        req.getRequestDispatcher("/pages/client/index.jsp").forward(req,resp);
    }
    /**
     * 处理分页功能: 根据查询到的数据，重新设置分页页码
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void pageByPrice(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1 获取请求的参数 pageNo 和 pageSize
        int pageNo = WebUtils.parseInt(req.getParameter("pageNo"), 1);
        int pageSize = WebUtils.parseInt(req.getParameter("pageSize"), Page.PAGE_SIZE);
        int min = WebUtils.parseInt(req.getParameter("min"), 0);
        int max = WebUtils.parseInt(req.getParameter("max"), Integer.MAX_VALUE);

        //2 调用BookService.page(pageNo，pageSize)：Page对象
        Page<Book> page = bookService.pageByPrice(pageNo,pageSize,min,max);

        //***目的是：我们切换页面时价格区也存在  设置url时(带有最大最小区间的参数传进去)
        StringBuilder sb = new StringBuilder("client/bookServlet?action=pageByPrice");//访问的参数传进去  后面追加
        // 如果有最小价格的参数,追加到分页条的地址参数中
        if (req.getParameter("min") != null) {
            sb.append("&min=").append(req.getParameter("min"));
        }
        // 如果有最大价格的参数,追加到分页条的地址参数中
        if (req.getParameter("max") != null) {
            sb.append("&max=").append(req.getParameter("max"));
        }
        page.setUrl(sb.toString());
        //3 保存Page对象到Request域中
        req.setAttribute("page",page);
        //4 请求转发到pages/manager/book_manager.jsp页面
        req.getRequestDispatcher("/pages/client/index.jsp").forward(req,resp);
    }

}
